Answer: A; 6.3%
Step-by-step explanation:
Problem 1
For the first problem, we first want to find y so that we can plug it into the expression.
We can use elimination method for the system of equations to solve.
3x+3y=21
3x-y=5
We subtract both equations to eliminate x.
4y=16 [divide both sides by 4]
y=4
Now that we know y, we can plug it into the expression.
[divide]
[subtract]

We know that the answer is A.
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Problem 2
For the second problem, we need to know how to calculate percent error. The formula for precent error is
. We know that the exact value is 80 because the buyer was supposed to given 80. 75 is the measured value because that was what the buyer was given.
[subtract]
[solve absolue value]
[divide]
[multiply]

Since the problem said to round to one decimal place, we know that the answer is 6.3%.
Here's a scenario that you can edit to your own advantage. You own a shirt shop. Each shirt sells for 15 dollars, and to make profit annually you need to sell $62,365 worth of shirts. If you've sold 2,000 shirts so far, how many shirts do you need to meet your quota. How many shirts on average per month would you have to sell?
Y+2=-4x+24
2=-4x-y+24
-22=-4x-y
Answer:
6√3 = x y =12
Step-by-step explanation:
Since the two sides of the triangles have equal angles then two sides have equal length
the sum of interior angles of triangles is 180° then the last angle is 60°
then the triangles have perfect sides of 12
y = 12
to calculate x
sin Ф = opposite/hypothenus
sin 60° = x/12
sin 60° = √3/2
( √3/2 ) x 12 = x
6√3 = x